The present invention relates to piezoelectric resonators with electrode films deposited on the crystal and with holding members holding the crystal at vibration nodes.
If such resonators are used in oscillator or filter circuits, small load, trimming or coupling capacitances are needed in most cases. As an example, FIG. 1 shows part of the oscillator circuit of a quartz-crystal watch module. 1 is a piezoelectric resonator, 2 is an amplifier, and C.sub.L1 and C.sub.L2 are load capacitors. The other divider stages present on an integrated-circuit chip used for such purposes, such as the IC 1115, are not shown. Because of the low supply voltage of such an integrated circuit, the load capacitors C.sub.L1 and C.sub.L2 can be realized therein as junction capacitances only with very great difficulty and with low Qs. Therefore, they had to be inserted into the circuit as discrete components. Similarly, filter circuits with piezoelectric resonators require capacitances which also had to be implemented with discrete components.